Online Dictionary of Invertebrate Zoology: Complete Work - Best Text

Online Dictionary of Invertebrate Zoology 75apical a. [L. apex, tip] Refers to the apex or top, as of a conicalor spherical structure.apical angle 1. (ARTHRO: Insecta) The angle of a wing at itsapex. 2. (MOLL: Gastropoda) In a plane through the axis,that angle subtended between two straight lines that touchadjacent whorls on opposite sides near the apex; identicalwith the spire angle if whorls increase at a regular rate.apical area 1. (ARTHRO: Insecta) see petiole. 2. (MOLL: Polyplacophora)The short part of the periostracum and tegmentumon the head and intermediate valves that is adjacentto the posterior dorsal edge of a valve and which extendsover the edge and onto the ventral side.apical carina (ARTHRO: Insecta) In ichneumonid Hymenoptera,the posterior transverse carina.apical cell 1. A cell situated at the apex of a structure distinguishedby location, shape, size and function. 2. (ARTHRO:Insecta) Apical testicular cell of Orthoptera, Dictyoptera,Diptera and Homoptera, and some Lepidoptera, that suppliesmitochondria to the spermatogonial cytoplasm duringspermatogenesis; Verson's cell; Versonian cell. 3. (NEMATA)An epithelial cell that forms the gonoduct wall.apical chamber (ARTHRO: Insecta) Pertaining to the germariumin the acrotrophic egg tubes.apical cross vein (ARTHRO: Insecta) A cross vein near theapex of the wing.apical field (ROTIF) The central anterior unciliated area of thecorona.apicalia n. [L. apex, tip] (GNATHO) Paired sensory cilia on thehead.apical lip notches (NEMATA) Indented lip margins at the junctionof the lips.apical margin (ARTHRO: Insecta) The outer margin of thewing. see costal margin, anal margin.apical organ A sensory organ located at the apex of trochophorelarvae and some cestodes.apical orifice (MOLL) An opening at the top or apex of a shell.apical plate An external sensory organ of a primitive nervous